Salarius Pharmaceuticals Inc.’s stock SLRX soared 33% in premarket trade Tuesday after the company said the U.S. Food and Drug Administration has lifted a partial clinical hold on a trial of a treatment for Ewing sarcoma, a rare and deadly form of cancer that occurs in bones or the soft tissue around bones. The treatment called seclidemstat, was being reviewed in a Phase 1/2 trial and had previously been granted Fast Track Designation, Orphan Drug Designation and Rare Pediatric Disease Designation. Ewing sarcoma typically occurs in children and young adults. “The FDA’s decision to remove the clinical hold puts us back…